1. Field of Invention
This invention relates generally to tools for the placement of fertilizer in soil, and more particularly to a manually operated hand tool to deposit a predetermined quantity of granular fertilizer in an associated mass in a hole created by the tool in soil.
2. Background and Description of Prior Art
It has become popular in ornamental horticulture to place discrete quantities of fertilizer in the earth for use by individual plants as opposed to general, somewhat homogeneous application of fertilizer over broad areas as is common in field horticulture for the propagation of botanical materials that usually are of the same type and occupy larger areas. In the recent past in placing such fertilizer it has become popular to use a consolidated fertilizer mass that has been formed into the shape of a stake with a pointed end that may be driven into the earth at the place desired for fertilizer application to thereafter disperse its fertilizer components into the surrounding soil. Such fertilizer stakes are simple and easy of use, but they are somewhat difficult to form so that they maintain their configuration to withstand physical forces placed upon them prior to and during placement and yet provide an appropriate release of the fertilizer materials from which they are formed or which they carry. Fertilizer stakes also are relatively expensive, often costing several times the amount of a similar quantity of dry, granular fertilizer containing the same amount of botanical nutrient material. The present invention seeks to provide a tool for placement of an associated mass of bulk, dry, granular fertilizer into the soil so that the granular material may be used in a fashion similar to fertilizer stakes at substantially lower cost for an equal amount of plant nutrients of the same availability.
Various hand tools for placement at a particular location of various material in and beneath the soil, especially seeds, other propagative plant material and fertilizer, have heretofore become known. To be practically useful, such tools must be easily insertable into the earth and this generally requires that a lower portion of the device that first contacts the earth be of a sharp or pointed nature to aid entry and moving soil out of the path of the tool as it moves therethrough. Various prior art devices have not provided a well defined, sharp lower portion, and especially a lower end that is of an acutely angulated wedge configuration to make insertion easy and allow its accomplishment with a minimum of force, to distinguish such tools from the acutely angulated wedge shape of my tool.
The force required for tool insertion into soil often is greater than can be reasonably accomplished by manual means. Prior tools have provided various foot supports, usually of a fixed nature, to allow a user's foot to aid insertion of the tool into soil. In distinction from such prior tools my tool provides a foot support that is pivotally mounted to allow it to be extended from a first storage position immediately adjacent the tool body to a second use position perpendicular to the tool body. This pivotal foot support gives the tool a more compact configuration in a storage mode or when the foot rest is not used and its positioning limits or allows determination of the depth of insertion into soil.
My tool defines a fertilizer reservoir that has a lower angulated portion carrying a pivotally mounted door that may be opened by interconnecting mechanical linkage operatively carried in the handle area in the upper portion of the tool. Other tools have provided pivotally openable bottom doors, but during placement in the earth of such prior tools it has been common that the door may be moved laterally and askew of its pivotal axis by reason of non-symmetrical forces caused on the door, as by irregularities in the earth at the place of insertion or the type of manipulation of the tool by a user. If this occurs, the door mounting structure may be damaged and ultimately rendered inoperative or broken. My tool differs from such prior devices by providing in a first species a door having a piano-hinge type mounting of some length and in a second species having side supports on each side of the door to extend upwardly about the adjacent reservoir portion to prevent the door from skewing or otherwise moving laterally to prevent damage to door mounting structures to make the door more durable and its operation more reliable.
it is desirable in a tool for the placement of granular fertilizer that predetermined amounts of fertilizer may be placed and that these predetermined amounts may be varied. Prior tools have often not provided means for measurement of material to be placed or those that have allowed such measurement often have not allowed variation of the measurement. The instant tool provides a material reservoir that carries only a single measured quantity of material to be placed at a single location, and in so doing, provides a compound reservoir with an adjustably movable sleeve to allow variation of reservoir volume while still allowing the reservoir to be easily filled from its upper portion by placing it in a bulk supply of granular material.
My invention lies not in any one of these features individually, but rather in the synergistic combination of all of its structures that necessarily give rise to the functions flowing therefrom as herein specified and claimed.